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Rotary Evolution · 09-30-2013, 10:47 AM

i always prefer a new harness over an old one but the following are steps i use to buy more life from marginal, old, original wiring:

convoluted tubing over areas that contact metal where it can rub through the harness or are draped over high heat areas.

most electrical tape you find just about anywhere is garbage. heat, fuel and oil unravel it as the adhesive melts or is compromised by fluids. don't even bother with vinyl electrical tape unless you know it can handle the job, such as an industrial grade wrap. self bonding silicone tape is better for a base insulator under convolute tubing or the actual friction covering.

for actually wrapping the outside of the harness i personally prefer either 3M friction tape or another brand of friction tape which contains more tar. it is self sealing, weather resistant, won't unravel, heat resistant and protects the harness quite well. if it comes in contact with oil or fuel it will get sticky but it won't be compromised.

if you're going to crimp versus solder, find the self sealing shrink tubes that will reinforce and seal the butt joint.

the biggest thing about wiring isn't so much the wire but the wire insulation. after years sitting in a 200F engine bay the insulation gets brittle and cracks, exposing the wires where they will begin to fray and oxidize. new wire is always preferred so that you can buy many more years before it begins to do the same. if an insulator is cracked and wires exposed but not compromised you can seal it up with liquid tape to buy a few more years without digging deeper into the harness and repairing it.

if you're stripping wiring from an old harness to repair it, hold a lighter under the insulation you're stripping for a few seconds to warm it up and then strip the wire. this helps you strip just the insulator without inadvertently taking half the core wires with it.

always double check to make sure your wiring isn't getting pinched under a bracket, resting on a sharp piece of metal or sitting exposed in an area with moving parts such as next to the throttle linkage.

09-30-2013, 10:47 AM	#2
Rotary Evolution rotaryevolution.net Join Date: Feb 2011 Location: Las Vegas, NV Posts: 248 Rep Power: 15	i always prefer a new harness over an old one but the following are steps i use to buy more life from marginal, old, original wiring: convoluted tubing over areas that contact metal where it can rub through the harness or are draped over high heat areas. most electrical tape you find just about anywhere is garbage. heat, fuel and oil unravel it as the adhesive melts or is compromised by fluids. don't even bother with vinyl electrical tape unless you know it can handle the job, such as an industrial grade wrap. self bonding silicone tape is better for a base insulator under convolute tubing or the actual friction covering. for actually wrapping the outside of the harness i personally prefer either 3M friction tape or another brand of friction tape which contains more tar. it is self sealing, weather resistant, won't unravel, heat resistant and protects the harness quite well. if it comes in contact with oil or fuel it will get sticky but it won't be compromised. if you're going to crimp versus solder, find the self sealing shrink tubes that will reinforce and seal the butt joint. the biggest thing about wiring isn't so much the wire but the wire insulation. after years sitting in a 200F engine bay the insulation gets brittle and cracks, exposing the wires where they will begin to fray and oxidize. new wire is always preferred so that you can buy many more years before it begins to do the same. if an insulator is cracked and wires exposed but not compromised you can seal it up with liquid tape to buy a few more years without digging deeper into the harness and repairing it. if you're stripping wiring from an old harness to repair it, hold a lighter under the insulation you're stripping for a few seconds to warm it up and then strip the wire. this helps you strip just the insulator without inadvertently taking half the core wires with it. always double check to make sure your wiring isn't getting pinched under a bracket, resting on a sharp piece of metal or sitting exposed in an area with moving parts such as next to the throttle linkage. __________________ http://rotaryevolution.net Last edited by Rotary Evolution; 09-30-2013 at 11:06 AM.